Vibration damping mount for machines



Oct. 14, 1952 L. E. STEIMEN VIBRATION DAMPING MOUNT FOR MACHINES Filed May 19, 1948 3 Sheets-Sheet 1 75 35 M 32 44 75 74 /4 Inventor 3b 42 32 lazur'encefi fi'lfeimen Oct. 14, 1952 sTElMEN 2,613,897

VIBRATION DAMPING MOUNT FOR MACHINES Filed May 19,1948 3 Sheets-Sheet 2 Deflection in Inches (O 8 F 5 S T 205 U {9 8 02 M A f\\ V l 5 I c 5 1 Deflection in Inches 6 f3 Inventor LawrenceESzez'men Byz's/lfizney Def lection in Inches Oct. 14, 1952 E. STEIMEN 2,613,397

VIBRATION DAMPING MOUNT FOR MACHINES Filed May 19, 1948 3 Sheets-Sheet 3 [nuenior LawrenceESzeimen Patented Oct. 14, 1952 VIBRATION DAMPIN G MOUNT FOR MACHINES Lawrence E. Steimen, Beverly, Mass, assignor to 7 United Shoe Machinery Corporation, Fleming! ton, N. J., a corporation of New Jersey Application May19, 1948, Serial No. 27,865 M 1 This invention relates to vibration-damping devices and is herein illustrated as embodied in mounts for machines of the press type.

Considerable difficulty has heretofore been experienced in connection with machines in the operation of which considerable pressure is applied to a work piece-over a short'period of time as in presses such as clicking machines or sole cutters, or in which sharp blows are delivered to a work piece as in fastening-driving machines. In such machines the forces resulting from the machine operation are suddenly transmitted-to the floor in such manner as. to produce undesirable vibrations usuallyaccompanied by considerable noise, in many instances seriouslyaffecting the floor and adjoining structures-and rendering working conditions unsatisfactory.

In view of the foregoing, it is an object of the present invention to provide an improved mount for machines which will be particularly eiiective in damping the forces applied to the floor resulting from the operation of machines ofthe impact typel It is proposed to accomplish this by limiting the amplitudes of the peak forces'transmitted and by extending the time cycle of application of all the forces involved so that the forces are gradually applied to the floor over-an appreciable length of time rather than as by a sudden blow.

To this end, and-as illustrated, there is provided a vibration-damping mount for machines in which there are a base and a plurality of yielding devices mounted in series and extending upwardly from the base, oneof the devices comprising a pair of vertical columns or struts, together with aplatform for supporting a machine and means operatively connecting-the platform to the upper ends of the columnsso static load of a machine supported .hponztheplatform, until they assume a shape in which they have a low springscale, there being provided means for arresting the deflections of'the' columns upon application of-apredetermined dynamic loading so that the-forces-subsequently applied act upon the yielding device ofcompara- 6 Claims. (01. 248-18) varying loads; and

tively large spring. scale in transmitting the forcesto thefloonzn It has' been. found that by supporting a machine'with amount of'the type aforementioned, positioned under eachleg of the machine, the amplitude of vibrations transmitted toithe floor is materially reduced to such an extent that the operation of the .1 machine has littleeffect upon the building structure supporting it' and the attendant noise lofoperation is markedly reduced. J

These and other. featuresof the invention are set forth' inthe following specificatiomare disclosed in the accompanying drawings, and'are pointed outinthe claims.

In thedrawings, I Fig. 1 is a perspective view of a-clicking machine supported on vibration-damping mounts which embody one form of my'iinvention;

I Fig. 2 is a viewin side elevation, partly in section, of one of the*mounts;. I v Fig. 3 is across sectional view takenalongthe lines III-'III" of: Fig. '2;-

Fig. 4 is a viewin vertical cross section through the mount;

Figs. .5 and-6 are diagrammatic views illustrate ing the operation of yielding columns under Fig. '7 is a diagrammatic view illustrating the operation of a column supported atits ends and a coilspring under compression, and the'operation of .such a column and a coil-spring inseries under varying loads. '1 The invention is illustrated, by way of example, in connection with a clicking. machine which, as shown in Fig. 1, comprises a frame Iii having four legs 12 which rest upon machine supports or. plat-. forms l4 forming parts of four shock mounts I6 embodying the invention. a

The machine itself is -.of a well-known type such as is disclosed in. United States Letters Pat-v ent No.-921,503, granted May 11, 1909, upon an application filed in the name of Arthur Bates,- and comprises a bed .11, supported upon the frame lit, and carryinga cutting block l8, upon whichqmaybe located sheet material [9, such as leather, to be operated, upon, anda die 20 resting upon thematerial. At one side of 'the'bed there is mounted for vertical reciprocation a'post 22 carryinga beam-24. which is movable heightwise of the block with the post and is also mov-: able laterally across thebloc-k about the axis of the post. Th post isuarranged to be reciprocated, 'upon depression of a starting handle 226, by mechanisms not'sho-wn, operatively connected a machine the beam is moved into position over the die' and depression of the starting handle initiates a pressure applying operation of the beam to force the die through the material to produce a blank. It is theinertia forces of the parts setirr motion and the forces dueto impact initiated bysuch an operation that the present invention seeks to damp by means of the shock mounts 15 supporting the machine.

As best shown in Figs. 2 and l, each of the mountsc'omprises a base plate 32' above" which is positioned the machine support or platform i4 secured to a flange 36 of a leg l-Z ofthe-machineby means of a nut 38 threaded upon a tube 40- slidable up and down on a pin 42 fastened to the central portion of the base 32. Atits upper extremity the tube 46 has secured thereto a spring abutment in the form of a plate 44 which rests" upon four stiff coil springs 46 bearing upon a springabutment or plate 4-8, slidably mounted on the tube 40, and carried uponheadsi't'flon the lower ends of rods -H? extending through the springs-1%: The rods areslidable inthe plate 44 and serve: to transfer the load applied to the abutmentzfifizby means of jamnuts 52', to a hanger inrthe form of a plate v5 i; Al threaded studi56 extends'upwardly from the hanger 5c and through anyopening 5% in a crosshead Gil-resting upon-the upper ends of. columns or struts 6'4.

The stud and the parts carried by it are support-- edby a, .nut58, on the: upper end of the studee'ngaging.,;lthe upper face of. the crosshead. I The underside of the crosshead 60 is provided with inset sockets 62 which receive the upper ends of columns fi l, the lower ends of which are inserted insimilar sockets- 66 setinthe'upper face of? the baseaplatefigy. 1.

The columns or struts 64; are in the form of slender rods preferably constructed of spring steel and are initially; bowed slightly prior toassembly in the mount. :This insures that the columns will yield appreciablyunderapplication of loads to their upper ends instead of: acting as rigid columns. By supporting the ends of. the columnsiinr the sockets 62 the columnsare stifiened sufiiciently that under the dead. load of the machine supported, they tend to assume a con-- figuration in which; they have a low spring-scale butz rg not,v flexed to. the point of failure.

.i'E-he constructionfiabovedescribed is such that the; entire load applied; to each machine leg. is supported upon the platforms l4 anditransmitted; through the various connections described, to

. the. bases 32. By adjusting the nutia on the stud- 56 the hanger 5t canbe. raised orl'owered; to, position the platform slightly, preferably a fe'wiinches; above thebase plate 32.

Means is provided for' varying the'ini'tialstiif ness; or the columns 64 so that each mount can beL-adju'stedi to difie'rerit static loads applied to the .7 platform without. materially varyingthe combined. spring scale of th columns and springs. To this end,'there is'provideda circular plate 683 threaded: upon the stud 5 6. Th'eplate is-ofa diameter such: that its periphery engages thezcolum'ns near their'upper' ends when the plate-is positioned close tothecrosshead 60'. V The plate 168 can be adjusted heightwise of the stud 56" anclicolumns 64 by rotating the plate on the stud. The plate: is arranged to be'locked in adiusted positi'on:by: a-ascrew" mounted in the crosshead; and havinga pin 'llwhich can be po-: sitioned in any: one of several holes 13 in the plate;- The scr'ewfill can be adjusted'heightwise of the columns =64 so that it extends to the plate in adjusted position, and can b locked in fixed position by nut 12. The stiffness of the columns is increased as the plate 68, in its adjusted position, engages the columns at greater distances from their upper ends.

The platforms I4, plate 44' and hanger 5d at I comparatively near to the central portions of the columns and consequently in proximity to the positions of maximum deflection of the columns is provided with a similar pair of slots 16 the side walls of which act as guides for movement of the columns radially of the plate. However, in this case the end portions 18 of the slots form abutments so positioned as to limit inward movement of columns beyond a predetermined amount, and upon contact with such end portions the yielding columns become substantially fixed, that is v they no longer bow inwardly upon application of ad ditional loads. The plate 48 is provided with ears 80, Fig. 2, adjacent to the slots 16, which support pins 82 extending across the slots and thus providing means preventing the columns 64 from leaving the slots when moved in an outward direction.

The mechanism of: each mount is protected. by a casing comprising an upstanding cylindrical tube 84, Fig. 2, having at the upper end thereof a cap 86 which extends over the upper end of an extension 88 of the rod 42, and is secured in.posi tion by a nut 90 threaded upon the rod 88 and a spring 92 surrounding the rod 88 and bearing against the underside of the cap 88 and against the upper end of the stud 5B. The tube 84 has an opening 85, for receiving the leg of a machine to be supported. q n V In the use of shock mounts of the construction above described, for example, in supporting a clicking machine, a mount is provided for each leg of the machine, the legs preferably being bolted to the platforms 14 of the mounts. The

. will then act successively through the platform H, thehtube 40, plate 44, coil springs 46, plate 48, rods 5!), hanger 54, stud 56, and crosshead 60, to load the bowed columns 64 which in turn will transmit the forces to the base 32 and to the floor. Under the static load the columns will be fur-. ther deflected inwardly until equilibrium is reached, the columns acting as springs, the stilt".- ness of which can be varied as required for different static loads over a considerable rangeby adjustment of the plate 68'heightwise of the col umns. I

When the machine thus supported is operated the inertia forces arising will be transmitted to n the floor initially through the coil springs and columns acting in series and with a comparative.- ly low spring scale, resulting in the transmission to the floor of the peak forces without impact. When the columns have been deflected until" they engage the inner walls 18 of the slots in the plates 48, the columns are stifiened until they are substantially rigid, and, thereafter, the coil springs act alone in damping the remaining forces trans mitted to the floor while the moving machine partsare brought to-rest 'Figs. 5, 6 and?- are for the purpose of ampli:

low combined spring scale. period of the cycle the deflection increases rapidly. When, however, the columns 64 engage the s" fying the explanation of the operation of the present construction. It is to be notedrthat if a vertical column unsupported laterally at its ends.

is subject to a vertically-applied load the column would, be deflected after the manner of the col umn I shown in the diagram of Fig. 5. Fig.5 also shows the characteristic curve of the deflection' of such a column in inches'plotted against the load in pounds. It will be noticed that this curve'rises rapidly to a certain point andthen turns downwardly which means that after a certain load is reached, deflection will increase rapidly without further application of load and the column will fail. In Fig. 6, diagram A shows a similar column I02 unsupported at its ends but having a resilient lateral support I03. The equivalent of this column is shown in diagram B in which the ends of the column I04 are laterally supported in sockets I05. The characteristic defiection curve of these columns is also shown in Fig. 6. In this connection it is to benoted that the deflection slowly increases for increases in load up to a particular value after which the deflection rapidly increases for small increments of load. In other words, a column laterally supported at its ends acts similarly to a stiff spring up to a certain point after which the deflection of the column increases rapidly with the load and the column deflects after the manner of a weak spring or a spring of low spring scale.

Use is made of this principle in the mounts above described, it being noted that the columns 64 are supported at their ends in the sockets 62 and 66. Thus if the stiffness of the columns is adjusted by means of a plate 68 to an amount such that the portion of the dead weight of a machine which is carried by a particular mount corresponds to the loading at about the point where the deflection curve starts to flatten out, the columns will be in condition to act as a weak spring upon the application of additional load resulting from the action of dynamic forces such as resulting from impact. Since the columns act as a weak spring and are in series with the coil springs 46 which are of high spring scale the resultant spring scale of the system will still be low and, consequently, the time cycle of transmission of the forces involved to the floor will be increased with the result that the peak forces arising from operation of the machine will be materially reduced.

As shown in Fig. '7, curve A represents the defiection plotted against the load for columns having laterally supported ends and corresponding to the columns 64 herein described. Curve B is a deflection curve of a stiff spring mounting such as spring 46. Curve C represents the deflection plotted against the loading of a typical shock mount as herein illustrated in which the column 64 and the coil springs 46 are in series. The point I06 on the curve C indicates the deflection of the system corresponding to a load of about 315 pounds representing the dead weight load applied to the platform. When additional load is applied to the mount due to operation of the machine the increased loading results in deflection between I and H18 during which the columns and springs act in series with a comparatively Thus, during this ends 18 of the slots in the plates 48 the columns are stiffened and do not appreciably deflect any further. The moving machine mass is then de- 6. celerated by action of the comparativelystiif coil springs 46 as indicated by' the' curve C-from the point lll8"upwardly and tothe right in Fig. '7.

Mounts of ;the construction above-described thus provide-means, readily adaptable,- to various types" of floor conditions for damping vibrations resulting from'the operation of the-machines supported, V U- Having thus described my invention whatgI claim as new and desire to secure by Letters Patent of the United States is l. 'A Vibration damping ,mount for machines comprisin a base, a plurality of bowed resilient struts extending upwardly from the base, a hanger supported by the upper endscf the struts, a platform suspended from the hanger, and springs operatively connecting the hanger and platform ,v for transmitting to the struts forces applied to the platform.

-2. A vibration damping mount for machines comprising a base, a plurality of inwardly bowed resilent rods extending upwardly from the base, ahanger supported by the upper ends of the rods, a platform suspended from the hanger, springs q operatively connecting the hanger and platform for transmitting to the rods forces applied to the platform, and a plate carried by the hanger and having portions engaging each of the rods for controlling the stiffness of the rods under a load applied to the platform.

3. A vibration damping mount for machines platform, a plate carried by the hanger having portions engaging each of the rods for controlling the stiffness of the rods under a load applied to the platform, and means for securing the plate selectively in predetermined positions heightwise of the rods for varying the stiffness of the rods under different loads. I

4. A vibration damping mount for machines comp-rising a base, a plurality of inwardly bowed resilient rods extending upwardly from the base, a hanger carried by the upper ends of the rods, a platform supported by the hanger, springs operatively connecting the platform and hanger for transmitting to the rods forces applied to the platform, and abutments located between the rods having portions for engaging the rods constructed and arranged to arrest the deflections of the rods upon application of a dynamic load to the platform.

5. A vibration damping mount for machines comprising a base, a plurality of inwardly bowed resilent rods extending upwardly from the base,

a hanger supported by the upper ends of the rods, a platform suspended from the hanger, springs operatively connecting the hanger and platform for transmitting to the rods forces applied to the platform, means carried by the hanger engaging each of the rods for controlling the stiffness of the rods under a static load applied to the platform, and abutments located between the rods for arresting deflections iof'the rods under a dynamic loadapplied to the platform.

6. A vibration-damping mount for machines comprising a base, a plurality of columns extending upwardlyfrom the base, a crosshead supported upon the upper ends of the columns, a hanger depending from the cross head, a plurality of rods slidably mounted in the hanger, means to: limiting downward movements of thg. rgcls' REEERENCE$ (211313511 rela tively t fi han qh 3 k ing abuf msznw The following references are of record in the riedat. t e lam: end of he-rodsa,. c@n1-2r1n& m 0mm patent? Y :T F Qutment located,- between the first-mentioned abutment and. he. anger, pl ra i z f sp i fi UNITE-Ii STATELSADATENTS? A between a i ga e nt i h th a la gahut N mb I Nam mcn s. as p tfcrm, and mea s pe at v y con- 1,9Q3, 5' 9- necting the platform and the sec ond-mentionegl 1,893 295 

